<text><span class="style10">he Universe and Cosmology (1 of 6)</span><span class="style7">The study of the universe, its overall structure and origin, is known as </span><span class="style26">cosmology</span><span class="style7">. In the 17th century, the universe was thought to be static, infinite and unchanging. Modern cosmology can be traced back to the 1920s when the American astronomer Edwin Hubble, using observations made by Vesto Slipher in 1912, showed that the space between galaxies is increasing and the universe is therefore expanding.There are several theories describing the origin and future of the universe. Among these, the big-bang theory is the most widely accepted. Opinions differ, however, as to the future of the universe. Some think that it will continue to expand for ever, whereas others believe that it will eventually end by collapsing in on itself in a big crunch.</span></text>
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<text><span class="style10">choes of the early universe</span><span class="style7">. This microwave map of the whole sky was created using data from the Cosmic Background Explorer (COBE) satellite. It shows minute variations (between blue and pink) in the cosmic microwave radiation some 300 000 years after the big bang, and may explain the origin of the `lumpiness' of the universe.</span></text>
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<text>ΓÇó TIMEΓÇó STARS AND GALAXIESΓÇó THE HISTORY OF ASTRONOMYΓÇó NEWTON AND FORCEΓÇó QUANTUM THEORY AND RELATIVITYΓÇó WAVE THEORYΓÇó OPTICSΓÇó ATOMS AND SUBATOMIC PARTICLES</text>